As is known, industrial aspiration plants today have to be in line with regulations described in the “ATEX” rules, i.e. the European Directive relating to materials and apparatus destined for use in potentially explosive atmospheres. The producers of aspirating plants and/or devices therefore have to provide apparatus that is adequate and the field of application of the rules involves gas and powders, and therefore work environments have to be purified by suitable aspirating plants. The Directive considers the risks of explosion of any type, electrical or otherwise, and classifies the apparatus into categories on the basis of the type of guaranteed protection, regulates the introduction of the essential safety requisites and oversees the production processes based on company quality systems. In this context the aspirating plants used in the companies take on an important role due to the very specific requests for prevention of risks deriving from potentially explosive atmospheres, and must also respond to essential safety and health requisites as they are apparatus destined to be used in potentially explosive atmospheres and/or in potentially explosive environments due to the presence of powders.
In this context, it seems clear that all actions involving abrasion operations generate a fine dust of abraded material which tends to diffuse into the environment, causing not only irritation but also potentially dangerous situations for the operator.
Further, the presence of dust during the abrading operations involves additional problems during the surface finishing of the manufactured product.
To cite a specific example, which is not intended to have a limiting value, in the sector of bodyworking and workshops, abrading devices are used for smoothing surfaces of painted products, and not for performing preparatory operations on the product for subsequent work operations. In this not-strictly industrial context, the problem of abraded dusts is particularly prominent. In fact, apart from additives which can be risky for health if breathed in or ingested, generally the parts of aluminium vehicles, when abraded, cause diffusion in the form of powder in the environment of metal particles which make the atmosphere in the working area inflammable and explosive. Today the market offers, and much use is made of, abrasive devices constituted by a support which exhibits an operating surface destined to receive a laminar abrading material, for example in paper form couplable to the support and exhibiting an active surface incorporated or clad in an abrasive material.
The support further exhibits gripping means for the user such that the user, when operating manually, can perform abrading operations for example on the bodywork element.
It is clear that this type of device is destined to generate much dust and abrading residues, with all the above-detailed problems.
To obviate at least a part of the above-cited drawbacks, use is made of abrading devices connected to electrical systems for aspirating the abraded material.
In any case, with the aim of generating sufficient aspirating forces, electric machines are today used which generate a depression, and which generically can substantially be called vacuum cleaners.
It is however evident that the presence of environments having a risk of explosion or fire, such as environments saturated with aluminium powders, are not very compatible with the presence of electric machines that can constitute the flashpoint for generation of the above-mentioned dangerous situations.
Further, the use of electrical aspiration systems of the above-described type leads in any case to a deterioration in terms of safety requisites to be respected internally of the workshop in such a way as to prevent the dangerous situations from actually obtaining.